SERIOUS FUN: CB are the first to tell you it's all for the partying crowd — but they take the party seriously.

In recent years, our random cultural generator has produced a new breed of DJ, blog-fueled crews who brazenly mix R&B with post-rock and reggaeton with pop punk as they host parties in cities from Seattle to Atlanta and cultivate their audience on-line. Yet these smartypants kids who put rap a cappella over indie-rock riffs have a precedent: Certified Bananas. Max Gitlen (from Albany) and Sam Posner (Cambridge) have had a residency at Central Square’s Enormous Room for more than a year, and in that Internet time imitators have sprouted up all over North America. Philly’s Hollertronix crew or Brooklyn’s the Rub have been doing their street-accepted DJ thing for longer, but CB, educated at Brown and still based in Providence, have done more to stretch the definition of DJ blends than their predecessors. In the process, they’ve redefined what a club night can be.

“There’s a lot of other DJ teams that do that as well,” Posner says over the phone from Providence. “But we come from more popular stuff, maybe even cheesy stuff. We play it only because we like it and that’s what we’re into.” What they’re into is putting Don Omar atop a Green Day riff, or working Soul Coughing inside Dirt McGirt. This month, the two are traveling across the US in support of their first mix CD, the self-released Sprang. The tour ends with their residency at Enormous Room this Friday, May 12, with special guest and fellow beatslinger Ghislain Poirier.

For almost two years, Posner and Gitlen have been cultivating their audience mostly on-line, through MP3 mixes hosted by friends like Lemon-Red and the Fader. But the time is ripe for a genuine Certified Bananas CD. “It feels like it’s been kind of leading up to this, so it’s very exciting,” Posner says.

Sprang is as smart as you’d expect from a pair of Ivy League grads. Yet in spite of the cheeky references and nimble cuts, it rocks the party. It’s hard to articulate the funk of a mix that layers 60 songs in 60 minutes, but here’s a taste: after the sixth minute, a jazzy Tortoise jam kicks in and, seconds later, Usher rides over the top.

“Yeah, it’s pretty crazy,” Posner says. “But that is my personal favorite part on the mix. They’re in the same key and the same tempo.” Posner, who also plays in the band Miss Fairchild, has an ear for harmony. “Max and I were listening to that track, and I started humming Usher to it,” he laughs. “We thought, ‘That sort of sounds similar, that’s pretty funny, I’m sure they’re not and I’m sure I’m making this up.’ But later we tried it just to see and basically nothing had to be done to either one of them. . . . We’re interested in matching things not only tempo-wise but melody-wise. Just because they are at the same tempo doesn’t mean it will sound good together. There’s another level in finding things that are actually in the same key.” What Posner describes happens time and time again on Sprang.

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